Saw-sharpening machine.



PATENTED APR. 14, 1908.

, J. "P, HEDSTROM. 7 MW SHARPENING MACHINE.

' APPLIGATTON FILED JAILZ Z, 1907.

UNITED STATES PATENT OFFICE.

JOHN PATRICK HEDSTROM, OF BIG RAPIDS, MICHIGAN, ASSIGNOR TO HANOHETTSWAGE WORKS, OF BIG RAPIDS, MICHIGAN, A FIRM.

SAW-SHARPENING MACHINE.

Patented April 14, 1908.

Serial No. 353,508.

To all whom it may concern:

Be it known that I, JOHN PATRICK HED- sTRoM, a citizen of the UnitedStates, residing at Big Rapids, in the county of Mecos'ta and State ofMichigan, have invented certain new and useful Improvements in Saw-Sharpening Machines; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

My invention relates to back feeding mechanism for saws, and while itmay be applicable in connection with other saws, I have chosen toillustrate one embodiment of the invention as applied to the backfeeding of band saws.

One object of my invention is the provision of means to relieve thedirect feed of a ortion of the work necessary to feed the saw forwardstep-by-step, thereby obtaining an easier and absolutely positive feed.

Another object isthe provision of a back feeding mechanism having fewparts of simple construction.

A further object is the provision of means for displacing a part atleast of the mechanism while it is still attached to the saw sharpeningmachine, in order to obtain more s ace.

A still further object is the provision of a back feed mechanism whichcan be attached to any of the usual types of saw sharpening machines nowon the market.

To these and other ends, therefore, my invention consists in certainnovel features and combinations, such as will be more fully describedhereinafter and particularly set forth in the claims.

In the accompanying drawings, Figure 1 is a perspective viewillustrating the applica tion of. my invention to a saw sharpeningmachine; Fig.2 is a view in side elevation of my invention and Fig. 3 isa top plan view thereof.

(A) indicates a saw sharpening machine of any suitable construction,equipped with the usual grinding wheel (B) and the oscillating feed bar(C) working in a slot (D) in the.

frame (E) of the machine. As the machine forms no part in thisinvention, further description thereof is unnecessary.

Secured to the oscillatory feed bar (C), is a hinge member, one leaf (1)of which is fastened to the bar, the remaining leaf being formed into apin (3) pivoted to the leaf (1), as at (4), the pin being of anysuitable shape.

A lever (5) is pivoted, as at (6) intermediate its ends, preferably, toa bracket (7) secured to the frame (E) near the back of the machine, thelever extending across the machine and capable of a horizontaloscillation.

The forward end of the lever is loosely connected to the hinge joint, asby being socketed at (8) to receive the pin (3),which is adapted totelescope thereinto and move back and forth therein. Thus it will beseen that the lever (5) extends at approximately right angles to thepath of oscillation of the feed bar (0), and as the feed bar moves backand forth it will cause the oscillation of the lever (5), the pin (3)moving in and out of the socket (8) by reason of the arc movement of thesocketed end of the lever which does not correspond with the rectilinearoscillation of the feed bar.

The rear end of the lever is provided with an arm (9) horizontallypivoted thereto, the end of the lever carrying wings (10) (10) embracingthe side edges of the arm to prevent lateral movement thereof relativeto the lever. The extreme outer or rear end of the arm is provided witha finger (11) adjustably secured thereto in anyconvenient manner, as bymeans of the set screw (12), such finger adapted to take betweenadjacent teeth of a band saw, and as the lever is oscillated, suchfinger will impart a movement to the saw to assist the feed bar (C) inmoving the saw step-bystep or tooth-by-tooth inposition to be engaged bythe grinding wheel (B).

The band saw is supported on the stands '(F) in such manner as toencircle the machine. The feed bar and its connected arts engage thatpart of the saw passing in front of the machine, and the back feedfinger (11) engages that part of the band saw assing behind the machine.As the feed ar moves forward to push the next tooth beneath the grindingwheel, the back feed finger will be moved in the opposite direction toassist the feed bar in moving the band saw step-bystep, the reversemovement of the feed bar causing the finger (11) to ride over thesucceeding tooth and drop behind it in readiness for the next forwardmovement of the feed bar.

When it is .not desired to use the back feed, the lever may be entirelydisconnected from the bracket and the feed bar, or the arm may.

if desired. The bracket is bent or offset to permit access to the pivotpoint of the lever.

Having thus fully disclosed my invention, What I claim as new is 1. Thecombination with a band saw sharpening machine provided with anoscillatory feed member, of a lever pivotally supported midway of itslength, the lever adapted to move in a horizontal plane, a suitableconnection between one end of the lever and the feed member, and a sawtooth engaging pawl on the opposite .end of the lever adapted to engagetie return lead of the saw to assist the feed member in moving the sawstep by step.

2. The combination with a band-saw sharpening machine provided with anoscillatory feed member, of a lever pivotally supported midway of itslength, the lever adapted to move in a horizontal plane, a suitableconnection between one end of the lever and the feed member, and asaw-tooth engaging the awl on the opposite end of the lever, the pawlhinged to the lever to move vertically and laterally immovable relativeto the lever.

3. A connection for two operative elements moving in planes transverseto each other comprising a telescoping pin hingesecured to one of thelevers, the remaining lever provided with a socket in which the pin isloosely received.

4. A connection for two movable elements comprising a hinge, one leaf ofwhich is secured to one of the elements, a pin on the remaining leaf ofthe hinge, the remaining element having a socket for loosely receivingthe pin.

In testimony whereof, I aHiX my signature in presence of two witnesses.

JOHN PATRICK HEDSTROM.

NVitnesses C. HARVEY KNAPP, L. B. I-IANoHETT.

